Circuit boards may include a plurality of heat-generating devices that must be cooled in order to operate within a specified operating temperature. If these heat-generating devices are not sufficiently cooled, then the devices can exhibit a decrease in performance or even permanently fail.
In some electronic systems, heatsinks are used to dissipate heat and cool heat-generating devices. Heatsinks facilitate heat exchange between the heat-generating device and the environment. Heat transfers from the heat-generating device to the heatsink. In some instances, fans direct airflow across the heatsink to increase thermal dissipation.
Packing density is also an important criterion in many electronic systems. One way to reduce the actual size of an electronic device is to more closely position the electrical components together. Electrical components within a circuit board, however, are generally already tightly confined, and additional space may not be readily available. Further, if heat-generating components are positioned more closely together, then heat must be sufficiently dissipated so the components properly operate.
Some electronic systems utilize several printed circuit boards with many different electronic components interconnected to the circuit boards. As these electronic systems decrease in size and increase in performance, heat dissipation and packing density become increasingly important.